1. Field of the Invention
This invention relates to an image recording method and apparatus for effecting the recording of an image on a recording medium. The term "image recording apparatus" covers a printer apparatus, a copying apparatus, an electronic typewriter and the like.
2. Related Background Art
In recent years, with the rapid development of the information industry, various information processing systems have been developed and image recording apparatuses suitable for the respective information processing systems have also been developed.
One of such image recording apparatuses is a thermosensitive transfer recording apparatus. This apparatus effects recording on a recording sheet by the use of an ink ribbon comprising a ribbon-like back-up member having applied thereto heat-meltable ink consisting of a coloring agent dispersed in a heat-meltable binder.
That is, said ink ribbon is superposed on the recording sheet so that the heat-meltable ink layer thereof contacts with the recording sheet, and the ink ribbon and the recording sheet are conveyed to between a thermal head and a platen, and pulse-like heat conforming to an image signal is applied from the back-up member side of said ink ribbon by the thermal head while, at the same time, the two are urged against each other to transfer the molten ink to the recording sheet, whereby an ink image corresponding to the application of heat is recorded on the recording sheet.
The above-described image recording apparatus has been widely used in recent years for its small size and light weight and noiselessness and its capability of recording images on plain paper.
However, the conventional thermosensitive transfer recording apparatus is not without a problem.
The problem is that in the conventional thermosensitive transfer recording apparatus, the transfer recording property, i.e., the quality of image, is greatly affected by the degree of surface smoothness of the recording sheet and the quality of image recording may be deteriorated in the case of a recording sheet having a low degree of smoothness although good image recording can be accomplished on a recording sheet having a high degree of smoothness.
Also, in the conventional thermosensitive transfer recording apparatus, when it is desired to obtain a polychromatic image, it is necessary to repeat transfer and superpose colors one upon another. Therefore, a plurality of thermal heads must be provided in the apparatus or the recording sheet must be subjected to complicated movements such as stoppage and backward feeding, and this leads to the problem that not only color misregistration is unavoidable, but also the entire apparatus becomes bulky and complex.
So, the applicant has invented an image recording method and a transfer recording medium which solve the problem peculiar to the aforedescribed conventional image forming apparatus and which are capable of recording images of high quality even on a recording medium having a low degree of surface smoothness and which, when applied for polychromatic recording, can provide a polychromatic image without causing the recording medium to effect complicated movements. The applicant filed patent applications in Japan by Japanese Patent Application No. 60-120080 (filed on June 3, 1985), Japanese Patent Application No. 60-120081 (filed on June 3, 1985), Japanese Patent Application No. 60-131411 (filed on June 17 1985), Japanese Patent Application No. 60-134831 (filed on June 20, 1985), Japanese Patent Application No. 60-150597 (filed on July 9, 1985), Japanese Patent Application No. 60-199926 (filed on Sept. 10, 1985) and Japanese Patent Application No. 60-250884 (filed on Nov. 11, 1985) Further, claiming the priority based on these Japanese patent applications, the applicant filed a U.S. application (Application No. 869,689 filed in U.S. on June 2, 1986) and an European application (Application No. 86107540.6, filed in Europe on June 3, 1986).
The present invention which will hereinafter be described is a further development over the aforementioned inventions covered by the Japanese applications, the U.S. application and the European application filed by the applicant. The present invention which will hereinafter be described permits suitable application of the image recording method and apparatus and the transfer recording medium made clear in the specifications of the aforementioned applications.